I would like to make a Robot

I would like to make a "Robot Butler". This robot will balance and walk upright. It will scan for items left on surfaces that match visual patterns of eating-utility (paper plates, empty-cups, plasticware, napkins), and upon command would gather them up and drop them into a known-location (or tagged) trash container. It could also pick up tagged items that can be delivered to flat table-surfaces in the same room, similar to somebody serving drinks or food to people. It would also answer calls and talk to the caller to ask to take a message, based on the owner's current activity.